Centrifugal blower wheel and method of forming



Feb. 23, 1960 L.` L. KEELEY CENTRIFUGAL BLOWER WHEEL AND METHOD 0F FORMING 2 Sheets-Sheet 1 Filed June 27, 1956 ATTORNEKS.

Feb. 23, 1960 L L KEELEY 2,925,953

CENTRIFUGAL BLOWER WHEEL AND METHOD OF' FORMING Filed June 27, 1956 2 Sheets-Sheet 2 /Mg MQ agg/4g' l fz-r fzs@ y M I L "w "I mmm# D Y fw? /a/ /NVENTRY 5y r W ATTORNEYS United States Patent O CENTRIFUGAL BLOWER WHEEL AND 'METHOD OF FRMING Lloyd L. Keeley, Wichita, Kans., assignor `to The Coleman Company, Inc., Wichita, Kans., a corporation of Application June `27, 1956, Serial No. 594,158

p 3 Claims. (Cl. 2311-134) This invention relates to a centrifugal blower wheel and method of forming the same, and more particularly the invention relates to the manufacture of a blower wheel in which the space between the blades is less than the blade width.

An object of the invention is to provide a method and means for forming a blower wheel wherein the blades are accurately interleaved with each other in the forming of a completed wheel or fan. A further object is to provide a structure in which the blower wheel is fabricated with a minimum of spot welding or other securing operations and in which an automatic spacing of the blades with respect to each other is brought about. A still further object is to provide a method of forming a blower wheel in which the staggered arrangement of the blades for interleaving is accomplished in an initial blanking step operation, the parts then being readily assembled to produce interleaving of the blades. Yet a further object is to provide a blower wheel of improvedI construction and which can be fabricated with greater certainty and with fewer operations than heretofore required. Other specific objects and advantages will appear as the specification proceeds.

The invention isshown in an illustrative embodiment by the accompanying drawings, in which- Figure l is a broken top plan view of a structure formed from a blank in an initial die-cutting operation; Fig. 2, a view similar to Fig. l but showing the blades in curved arrangement; Fig. 3, an edge view of the structure shown in Fig.y 2; Fig. 4, a top plan view of the blower structure after one part of the structure shown in Fig. 2 has been folded upon the other; Fig. 5, an edge view of the structure shown in Fig. 4; Fig. 6, a broken enlarged edge view of the completed blower wheel structure after the same has been formed into cylindrical shape; Fig. 7, a broken perspective view of the wheel structure; and Fig. 8, a detail sectional View, the section being taken as indicated at line 8 8 of Fig. 6.

In the structure shown in Fig. l, A designates a piece or strip of material formed from a metal blank in an initial die-cutting operation. In this operation, there is provided a central wide panel or rim 10 .which is adapted subsequently to bevfolded along the longitudinal perforated line 1.1. Spaced laterally from the central panel 10 are the side panels 12 and 13. Extending between the panel 10 and the side panel 12 are the blade blanks 14, and extending between the panel 10 and the side panel 13 are the blade blanks 15. In the initial diecutting operation, the blanks 14 are formed in staggered or non-aligned positions with respect to the blade blanks 15.

The blade blanks 14 are formed into the curved blades 14a, 'and similarly the blanks 1S are formed into the curved blades 15a, as illustrated in Fig. 2, and it will be observed that the blades :15a are accurately aligned with the central portions of the spaces between the blades 14a so that when the central panel 10 is folded upon itself along the dotted line 11, the blades 15a are interleaved l 16, or otherwise secured together.

' structure, the panel 10 provides an upper rim 10a and a 2,925,953 Patented Feb. 23, 1960 s `2 with the blades 14a, as illustrated best in Figs. 3,k 4 and 5 On the one side where the rim is formed by the panel 10, the rim portions are integrally connected, while on the other side the rim portions are formed by the superposed side rims 13 and 12, which may be spot welded at In the folded-over lower rim 10b.

It will be understood thatl in fabricating operations, the structure as shown in Fig. l may be continuously formed and subsequently cut into strips of the desired length `for forming the blower wheels, the ends of the strips being united by welding or by any other suitable means.

In the foregoing process, the construction provides positive positioning of one blade configuration with respect to the second blade configuration, while at the same time only a few spot welds are required to secure the two blade sections together. Further, it is possible in this type of construction to provide a final Wheel in which the edge surfaces of all blades coincide with a single wheel circumference; in other words, the vanes can be made so as to have a constant inner and outer circumference, every other blade being neither shorter nor longer. Also, the two continuous rims or rails of each blade section form a more rigid construction after edge rolling.

Operation In the operation of the invention, the structure A is stamped from a single sheet which is preferably perforated or weakened along the longitudinal fold line 11. The blades are spaced alternately on the sheet so that they may pass through the openings when the sheet is folded. The blades may be formed up on one side and down on the other so that they will all be facing in the same direction when the sheet is folded along the perforated or weakened fold-line 11. The curved form of the blades 14a and 15a may be brought about at any stage in the operation, and, when the panel 10 is folded upon itself to provide an upper integral rim 10a and a lower integral rim 10b, the rim 13 is brought into overlapping relation with the rim 12 as the blades 15a become interleaved with the blades 14a. Spot welding or other securing means may be employed then to unite rims 13 and 12 and, if desired, the rims then may be subjected to edge rolling to produce a highly rigid construction. In the foregoing operation, in which the blades are formed and the structure folded and the strip turned into a circular shape to produce the wheel, the ends of the strip may be united to complete the structure. While I have described various steps in successive timed relation, it will be understood that many of these steps may be varied with respect to each other in their timed relation.

In the foregoing operation, accuracy of positioning is automatically brought about as a result of the initial blanking or die-cutting operation and with a minimum of welding and a minimum of parts to be handled, the

Y blades being formed with self-spacing and accurate relation with respect to each other in a minimum of steps.

While in the foregoing specification I have set forth a specific structure and procedure in considerable detail for the purpose of illustrating an embodiment of the invention, it will be understood that such details of struc ture or procedure may be varied widely by those skilled in the art without departing from the spirit of my invention.

I claim:

l. A blower wheel, comprising a Wide rim folded upon itself and circularly curved in its longitudinal dimension, each folded portion of the rim having integral blades extending therefrom; the blades f one portion beiig staggered with respect to thefblades of the other rim portion and interveaved therewith, and means for uniting the outer end portions of the blades. Y

.2. The strueture of clirn, y1, ,in which ,the outer ,end portions of the bldes are equipped with rir'n's whih are secured together. ,y

3. A blade strip adapted for ,the formingof blcwnei'- Wheel, Comprising a centrl panelperforated etlally along longitudinal linev rd folded upon lsaid line lto form integral upper and vlower rims, said folded ,panel being longitudinally` cireulrly: erved, blades, vftirrnel integrally with said upper',l nd lower rims end. extending laterally therefrom in staggered,relation,v with the bladesl of one rirn extending between the blds of the other; nd

side rims integrally connected to the outer ends of said blades and secured together in superposed relation.

References Cited in the le of this patent UNITED STATES PATENTS 2,684,521 Morrison .'.ii 2,703,045 Gilbert et al. 

